Add a facility to register a range of physical addresses to be used

for allocation of fictitious pages, for which PHYS_TO_VM_PAGE()
returns proper fictitious vm_page_t. The range should be de-registered
after consumer stopped using it.

De-inline the PHYS_TO_VM_PAGE() since it now carries code to iterate
over registered ranges.

A hash container might be developed instead of range registration
interface, and fake pages could be put automatically into the hash,
were PHYS_TO_VM_PAGE() could look them up later. This should be
considered before the MFC of the commit is done.

Sponsored by:	The FreeBSD Foundation
Reviewed by:	alc
MFC after:	1 month

1 files changed, 4 insertions, 0 deletions

diff --git a/sys/vm/vm_phys.h b/sys/vm/vm_phys.h
index 047e4a9..902659b 100644
--- a/sys/vm/vm_phys.h
+++ b/sys/vm/vm_phys.h
@@ -57,6 +57,10 @@ vm_page_t vm_phys_alloc_contig(u_long npages, vm_paddr_t low, vm_paddr_t high,
     u_long alignment, vm_paddr_t boundary);
 vm_page_t vm_phys_alloc_freelist_pages(int flind, int pool, int order);
 vm_page_t vm_phys_alloc_pages(int pool, int order);
+int vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
+    vm_memattr_t memattr);
+void vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end);
+vm_page_t vm_phys_fictitious_to_vm_page(vm_paddr_t pa);
 void vm_phys_free_contig(vm_page_t m, u_long npages);
 void vm_phys_free_pages(vm_page_t m, int order);
 void vm_phys_init(void);